From 771a794c0a3c3e7f0d86cc34be4f9537e8c0a20c Mon Sep 17 00:00:00 2001
From: Yuan Can <yuancan@huawei.com>
Date: Mon, 14 Nov 2022 08:26:39 +0000
Subject: [PATCH] fm10k: Fix error handling in fm10k_init_module()
Git-commit: 771a794c0a3c3e7f0d86cc34be4f9537e8c0a20c
Patch-mainline: v6.1-rc8
References: git-fixes

A problem about modprobe fm10k failed is triggered with the following log
Given: 

 Intel(R) Ethernet Switch Host Interface Driver
 Copyright(c) 2013 - 2019 Intel Corporation.
 debugfs: Directory 'fm10k' with parent '/' already present!

The reason is that fm10k_init_module() returns fm10k_register_pci_driver()
directly without checking its return value, if fm10k_register_pci_driver()
failed, it returns without removing debugfs and destroy workqueue,
resulting the debugfs of fm10k can never be created later and leaks the
workqueue.

 fm10k_init_module()
   alloc_workqueue()
   fm10k_dbg_init() # create debugfs
   fm10k_register_pci_driver()
     pci_register_driver()
       driver_register()
         bus_add_driver()
           priv = kzalloc(...) # OOM happened
   # return without remove debugfs and destroy workqueue

Fix by remove debugfs and destroy workqueue when
fm10k_register_pci_driver() returns error.

Fixes: 7461fd913afe ("fm10k: Add support for debugfs")
Fixes: b382bb1b3e2d ("fm10k: use separate workqueue for fm10k driver")
Signed-off-by: Yuan Can <yuancan@huawei.com>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 drivers/net/ethernet/intel/fm10k/fm10k_main.c | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/intel/fm10k/fm10k_main.c b/drivers/net/ethernet/intel/fm10k/fm10k_main.c
index 4a6630586ec9..fc373472e4e1 100644
--- a/drivers/net/ethernet/intel/fm10k/fm10k_main.c
+++ b/drivers/net/ethernet/intel/fm10k/fm10k_main.c
@@ -32,6 +32,8 @@ struct workqueue_struct *fm10k_workqueue;
  **/
 static int __init fm10k_init_module(void)
 {
+	int ret;
+
 	pr_info("%s\n", fm10k_driver_string);
 	pr_info("%s\n", fm10k_copyright);
 
@@ -43,7 +45,13 @@ static int __init fm10k_init_module(void)
 
 	fm10k_dbg_init();
 
-	return fm10k_register_pci_driver();
+	ret = fm10k_register_pci_driver();
+	if (ret) {
+		fm10k_dbg_exit();
+		destroy_workqueue(fm10k_workqueue);
+	}
+
+	return ret;
 }
 module_init(fm10k_init_module);
 
-- 
2.35.3